A polymerizable complex (PC) technique was utilized to prepare fine powders of high purity BaTinO2n + 1 with n = 1, 2 and 5 at lower temperatures than those used for the ordinary solid-state reaction procedure. The formation of pure BaTinO2n + 1 occurred when precursors obtained from PC-derived gel materials were heat-treated at 800-900°C in static air for 2 h. BaTinO2n + 1 powders were subsequently converted to RuO2-loaded materials, and their photocatalytic activities for the decomposition of water were examined. While the RuO2-BaTi2O5 (n = 2) and RuO2-BaTi5O11 (n = 5) materials exhibited photocatalytic activity for water decomposition into H2 and O2 in approximately stoichiometric amounts (H2:O2 = 2:1) under UV light irradiation with specific hydrogen gas evolution rates of 125 and 52 μmol h-1 g-1, respectively, the RuO2-BaTiO3(n = 1) exhibited a very low activity of less than 1 μmol h-1 g-1. The lack of a significant occurrence of photocatalysis in BaTiO3 was explained in terms of its crystal structure possessing only a very small polyhedral distortion.
ASJC Scopus subject areas